1. Technical Field
The present disclosure relates to a technology for generating a bandgap reference voltage using a leakage current, and more particularly, to a low-power bandgap reference voltage generator using a leakage current, which is capable of generating a voltage proportional to the absolute temperature using a leakage current flowing in a state where a transistor is turned off, and operating at low power using an amplifier which operates below a threshold voltage.
2. Related Art
In general, a reference voltage generator refers to a circuit which generates a constant reference voltage in a semiconductor integrated circuit, regardless of an external environmental variation such as a surrounding temperature, process condition or external supply voltage.
Among a variety of reference voltage generators, a bandgap reference voltage generator refers to a circuit which independently outputs a constant reference voltage regardless of a surrounding temperature, supply voltage or process variation.
Recently, portable terminals operated through a battery have widely spread. Such portable terminals are required to operate at low power and low voltage. Thus, the bandgap reference voltage generator is also required to operate at low power and low voltage.
However, the conventional bandgap reference voltage generator has several obstacles to the operation at low power and low voltage. For example, the conventional bandgap reference voltage generator uses two operating points. For this configuration, a start-up circuit is used. The start-up circuit serves to help the bandgap reference voltage generator to maintain a stable operating point, when the bandgap reference voltage generator is switched from an idle mode to an operation mode or switched from the operation mode to the idle mode.
Since the conventional bandgap reference voltage generator uses the start-up circuit, there are difficulties in operating the conventional bandgap reference voltage generator at low power and low voltage.